The present invention is directed generally to a new rodenticide composition that is universally acceptable to rats and mice and more particularly to a mixture of raw dried sweet corn as a natural palatable inert ingredient along with an effective yet safe active ingredient.
Rodents have been a serious and age-old problem for mankind. Ironically, rats and mice have more of a tendency to thrive in inhabited areas just where man does not want them. As a result of this cohabitation, man is at constant war with the rodent population and for good reason. The problems that rodents cause are numerous. Foremost are the diseases that rodents transmit to mankind by actual bites and by contamination through their urine and feces. Secondly, the economic loss caused by rats and mice is tremendous. It is estimated that about 1/5 of the foodstuffs planted every year in the world are never eaten by people because of the damage caused by rodents. In fact, in some parts of the world, rodents make it impossible to grow some very much needed crops. Rodents not only cause problems with the growing and producing of crops and foodstuffs but they also cause serious problems with processed products. The amount of contamination of food by rats and mice is easier understood when one looks at the figures. One rat alone will produce approximately 25,000 droppings per year while one mouse will produce about 18,000 droppings per year.
Rats and mice also cause millions of dollars of damage to structures and materials every year. They have an inherent sense of gnawing. As a result of this physical trait, property damage can be extensive and dangerous. Many of the fires caused by "unknown origin" in the United States are believed to have been caused by rodent damage to electrical wiring.
One method of controlling the rodent population is by using rodenticides. Many different rodenticides have been devised and made commercially available to date. A typical rodenticide includes an inert food base, an active ingredient and various additives. Such grains as field corn and oats have been used as ingredients of rodenticide food bases. "Field corn" is broadly used herein to collectively refer to the various types of corn which are normally grown for feeding livestock, such as yellow dent corn, flint corn and soft corn and, in some cases, grain sorghum. Likewise, field corn is to be distinguished from sweet corn which is referred to by its botanical name Zea Mays Saccharata and by International Feed No. 40297. Known rodenticides have had certain limitations, however, relating primarily to effectiveness and safety.
In laboratory tests reported in a publication of the National Pest Control Association, a variety of foods from several different main groups or classes were tested for their relative preference or acceptance by Norway rats. The main groups included meats, vegetables, fish, fruits, liquids and grains and seeds. In the vegetable class, those ranked in the order of their highest degree of acceptance were frozen sweet corn, frozen green peas, canned sweet corn, carrots, sweet potatoes, butternut and acorn squash. Likewise, the preferred grains and seeds included breakfast rolled oats, freshly ground whole yellow field corn, steel-cut oat groats, brown/white rice, degerminated yellow corn meal and hominy grits.
Several of the above-mentioned foods, and particularly the vegetables such as frozen sweet corn and green peas and canned sweet corn, have been considered as unsuitable ingredients for rodenticides because of short shelf life. Rodenticides are typically subjected to storage stability tests wherein a batch of the rodenticide is tested periodically such as monthly over a one year period to determine if the food base is shelf stable and if the active ingredient is still active.
Rodent acceptance depends upon a combination of texture, taste and odor. Whereas odor can help attract a rodent to a bait, the final test of consumption is the palatability of the material determined by its taste and texture.
A common solution for improving rodenticides is to include additives. Additives may be included for many different reasons but often result in increased acceptance of the rodenticide. Additives may include an odor-producing attractant, binders for holding the bait particles together, coloring agents, emetics for causing non-target animals to regurgitate the bait, enhancers such as sugar, preservatives and, to a limited extent, potentiating agents. Such additives can increase manufacturing costs without an attendant increase in the acceptance rate for the rodenticide product.
An important design criteria for a rodenticide is its relative safety. Warfarin has been widely accepted over the last two decades as an indirect anticoagulant rodenticide for rat control in urban and rural areas because of the safety to non-target animals and high control efficiency to rodents. Its effectiveness is limited, however, since a long treatment period, over two weeks, is required to obtain satisfactory results and Warfarinresistant rats and mice have been discovered in the United States and abroad. Acute active ingredients, such as strychnine, are available but they are generally considered too dangerous for common usage. A second generation of active ingredients has been developed which require only a single feeding so that the rodents do not have to eat as much of the rodenticide but these can also pose safety threats to humans and non-target animals.
Accordingly, a primary object of the present invention is to provide an improved rodenticide.
Another object is to provide a rodenticide which is relatively safe to use and which is highly effective for rodent control.
Another object is to provide such a rodenticide which is simple and economical to formulate and produce.
Another object is to provide a rodenticide which uses dried natural sweet corn as the inert ingredient thereof.
Another object is to provide a highly effective rodenticide which is free of additives.
Another object is to provide a safe rodenticide for which a known antidote is available for the active ingredient thereof.
Finally, an object of the invention is to provide an improved rodenticide which is simple in formulation, economical to produce and effective in operation.